-
The Lancet. Diabetes & Endocrinology Jun 2020Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are associated with low birthweight, but important knowledge gaps remain regarding the effect of subclinical thyroid function test abnormalities on birthweight-both in general and during the late second and third trimester of pregnancy. The aim of this study was to examine associations of maternal thyroid function with birthweight.
METHODS
In this systematic review and individual-participant data meta-analysis, we searched MEDLINE (Ovid), Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and Google Scholar from inception to Oct 15, 2019, for prospective cohort studies with data on maternal thyroid function during pregnancy and birthweight, and we issued open invitations to identify study authors to join the Consortium on Thyroid and Pregnancy. We excluded participants with multiple pregnancies, in-vitro fertilisation, pre-existing thyroid disease or thyroid medication usage, miscarriages, and stillbirths. The main outcomes assessed were small for gestational age (SGA) neonates, large for gestational age neonates, and newborn birthweight. We analysed individual-participant data using mixed-effects regression models adjusting for maternal age, BMI, ethnicity, smoking, parity, gestational age at blood sampling, fetal sex, and gestational age at birth. The study protocol was pre-registered at the International Prospective Register of Systematic Reviews, CRD42016043496.
FINDINGS
We identified 2526 published reports, from which 36 cohorts met the inclusion criteria. The study authors for 15 of these cohorts agreed to participate, and five more unpublished datasets were added, giving a study population of 48 145 mother-child pairs after exclusions, of whom 1275 (3·1%) had subclinical hypothyroidism (increased thyroid stimulating hormone [TSH] with normal free thyroxine [FT]) and 929 (2·2%) had isolated hypothyroxinaemia (decreased FT with normal TSH). Maternal subclinical hypothyroidism was associated with a higher risk of SGA than was euthyroidism (11·8% vs 10·0%; adjusted risk difference 2·43%, 95% CI 0·43 to 4·81; odds ratio [OR] 1·24, 1·04 to 1·48; p=0·015) and lower mean birthweight (mean difference -38 g, -61 to -15; p=0·0015), with a higher effect estimate for measurement in the third trimester than in the first or second. Isolated hypothyroxinaemia was associated with a lower risk of SGA than was euthyroidism (7·3% vs 10·0%, adjusted risk difference -2·91, -4·49 to -0·88; OR 0·70, 0·55 to 0·91; p=0·0073) and higher mean birthweight (mean difference 45 g, 18 to 73; p=0·0012). Each 1 SD increase in maternal TSH concentration was associated with a 6 g lower birthweight (-10 to -2; p=0·0030), with higher effect estimates in women who were thyroid peroxidase antibody positive than for women who were negative (p=0·10). Each 1 SD increase in FT concentration was associated with a 21 g lower birthweight (-25 to -17; p<0·0001), with a higher effect estimate for measurement in the third trimester than the first or second.
INTERPRETATION
Maternal subclinical hypothyroidism in pregnancy is associated with a higher risk of SGA and lower birthweight, whereas isolated hypothyroxinaemia is associated with lower risk of SGA and higher birthweight. There was an inverse, dose-response association of maternal TSH and FT (even within the normal range) with birthweight. These results advance our understanding of the complex relationships between maternal thyroid function and fetal outcomes, and they should prompt careful consideration of potential risks and benefits of levothyroxine therapy during pregnancy.
FUNDING
Netherlands Organization for Scientific Research (grant 401.16.020).
Topics: Birth Weight; Female; Gestational Age; Humans; Hypothyroidism; Infant, Low Birth Weight; Infant, Newborn; Pregnancy; Pregnancy Complications; Thyroid Function Tests; Thyroid Gland
PubMed: 32445737
DOI: 10.1016/S2213-8587(20)30061-9 -
Endocrine Nov 2023To investigate whether maternal cigarette smoking during pregnancy is a risk factor for developing GDM. (Meta-Analysis)
Meta-Analysis
PURPOSE
To investigate whether maternal cigarette smoking during pregnancy is a risk factor for developing GDM.
METHODS
MEDLINE, Scopus, CENTRAL and Google Scholar databases were searched from inception to December 2022 to identify eligible original articles. A systematic review and meta-analysis (weighted data, random-effects model) were performed. The primary outcome was the development of GDM in pregnant women. The results were expressed as odds ratios (OR) with 95% confidence interval (CI) (inverse variance method). Subgroup analysis was planned according to the maternal smoking status and GDM diagnostic criteria. Statistical heterogeneity was checked with the Chi-squared (Chi) test and the I index was used to quantify it. The studies were evaluated for publication bias.
RESULTS
Thirty-five studies, including 23,849,696 pregnant women, met the inclusion criteria. The pooled OR of smoking during pregnancy compared with non-smoking (never smokers and former smokers) was 1.06 (95% CI 0.95-1.19), p = 0.30; I = 90%; Chi = 344; df=34; p < 0.001. Subgroup analysis was performed according to the two-step Carpenter-Coustan diagnostic criteria, due to the high heterogeneity among the other applied methods. The pooled OR for the Carpenter-Coustan subgroup was 1.19 (95% CI 0.95-1.49), p = 0.12; I = 63%; Chi = 27; df=10; p < 0.002. Further subgroup analysis according to maternal smoking status was not performed due to missing data.
CONCLUSION
There is no evidence to support an association between maternal cigarette smoking during pregnancy and the risk for GDM. Universally accepted diagnostic criteria for GDM must be adopted to reduce heterogeneity and clarify the association between smoking and GDM.
Topics: Pregnancy; Female; Humans; Diabetes, Gestational; Cigarette Smoking
PubMed: 37347387
DOI: 10.1007/s12020-023-03423-6 -
Acta Obstetricia Et Gynecologica... Jul 2022The association between intrahepatic cholestasis of pregnancy (ICP) and maternal lipid metabolism remains unknown. This systematic review and meta-analysis aimed to... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
The association between intrahepatic cholestasis of pregnancy (ICP) and maternal lipid metabolism remains unknown. This systematic review and meta-analysis aimed to evaluate the association between ICP and maternal lipid metabolism.
MATERIAL AND METHODS
We systematically searched Medline, Embase and the Cochrane Library (up to December 11, 2021) to identify relevant studies that investigated ICP and maternal plasma lipid concentrations. The weighted mean difference (WMD) and 95% confidence intervals (CI) were calculated using random-effects models. A subgroup analysis was conducted to identify the potential sources of heterogeneity. Potential publication bias was tested using funnel plots and the Egger's and Begg's tests. This meta-analysis was registered with PROSPERO (CRD42021293783).
RESULTS
Eleven studies were included in this qualitative analysis. A random-effects meta-analysis of data from the final included nine studies (n = 786 participants) showed a significant association between ICP and maternal dyslipidemia, with elevated levels of triglycerides (WMD, 0.67 mmol/L; 95% CI 0.39-0.95; P < 0.001), total cholesterol (WMD, 1.08 mmol/L; 95% CI 0.58-1.58; P < 0.001), low-density lipoprotein cholesterol (WMD, 1.08 mmol/L; 95% CI 0.53-1.64; P < 0.001), and reduced high-density lipoprotein cholesterol level (WMD, -0.38 mmol/L; 95% CI -0.53 to -0.23; P < 0.001) vs normal pregnancies.
CONCLUSIONS
The present study's findings support an association between ICP and maternal dyslipidemia. ICP pregnancies have dysregulated lipid metabolism vs normal pregnancies.
Topics: Cholestasis, Intrahepatic; Cholesterol; Dyslipidemias; Female; Humans; Pregnancy; Pregnancy Complications
PubMed: 35599353
DOI: 10.1111/aogs.14380 -
Journal of Reproduction & Infertility 2023Cell-free fetal DNA (cffDNA) is a novel screening method for fetal aneuploidy that facilitated non-invasive prenatal testing (NIPT) through analysis of cffDNA in... (Review)
Review
BACKGROUND
Cell-free fetal DNA (cffDNA) is a novel screening method for fetal aneuploidy that facilitated non-invasive prenatal testing (NIPT) through analysis of cffDNA in maternal plasma. However, despite increased sensitivity, it has a number of limitations that may complicate of its results interpretation. Therefore, elucidating factors affecting fetal fraction, as a critical limitation, guides its clinical application.
METHODS
In this report, systematic search was carried out through PubMed, Web of Science, and Scopus databases until February 11, 2022 by using keywords consist of "noninvasive prenatal screening", "NIPT", "noninvasive prenatal", "cell free DNA" and "fetal fraction". The articles were screened for eligibility criteria before data extraction.
RESULTS
A total of 39 eligible studies, most published between 2010 and 2020, were included. Based on the results of studies, a negative correlation between maternal age and BMI/body weight with fetal fraction was found. Furthermore, LDL, cholesterol, triglyceride level, metformin, heparin and enoxaparin therapy, hemoglobin-related hemoglobinopathies, and physical activity showed to have negative associations. Interestingly, it seems the ethnicity of patients from South and East Asia has a correlation with fetal fraction compared to Caucasians. Positive correlation was observed between gestational age, free β-hCG, PAPP-A, living in high altitude, and twin pregnancy.
CONCLUSION
Considering each factor, there was significant inconsistency and controversy regarding their impact on outcomes. Indeed, multiple factors can influence the accuracy of NIPS results, and it is worth noting that the impact of these factors may vary depending on the individual's ethnic background. Therefore, it is important to recognize that NIPS remains a screening test, and comprehensive pre- and post-NIPS counseling should be conducted as part of standard clinical practice.
PubMed: 38164433
DOI: 10.18502/jri.v24i4.14149 -
BMJ Open Feb 2022Urine pregnancy tests are often inaccessible in low-income settings. Expanded provision of home pregnancy testing could support self-care options for sexual and... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
Urine pregnancy tests are often inaccessible in low-income settings. Expanded provision of home pregnancy testing could support self-care options for sexual and reproductive health and rights. We conducted a systematic review of pregnancy self-testing effectiveness, values and preferences and cost.
DESIGN
Systematic review and meta-analysis using the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach.
DATA SOURCES
PubMed, CINAHL, LILACS and EMBASE and four trial registries were searched through 2 November 2020.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
We included trials and observational studies that compared urine self-testing for pregnancy to health worker-led pregnancy testing on effectiveness outcomes; quantitative and qualitative studies describing values and preferences of end users and health workers and costs of pregnancy self-testing.
DATA EXTRACTION AND SYNTHESIS
Two independent reviewers used standardised methods to search, screen and code included studies. Risk of bias was assessed using the Cochrane Collaboration and Evidence Project tools. Meta-analysis was conducted using random effects models. Findings were summarised in GRADE evidence profiles and synthesised qualitatively.
RESULTS
For effectiveness, four randomised trials following 5493 individuals after medical abortion showed no difference or improvements in loss to follow-up with home pregnancy self-testing compared with return clinic visits. One additional trial of community health workers offering home pregnancy tests showed a significant increase in pregnancy knowledge and antenatal counselling among 506 clients. Eighteen diverse values and preferences studies found support for pregnancy self-testing because of quick results, convenience, confidentiality/privacy, cost and accuracy. Most individuals receiving pregnancy self-tests for postabortion home management preferred this option. No studies reported cost data.
CONCLUSION
Pregnancy self-testing is acceptable and valued by end users. Effectiveness data come mostly from articles on postabortion care, and cost data are lacking. Greater availability of pregnancy self-tests, including in postabortion care and CHW programs, may lead to improved health outcomes.
PROSPERO REGISTRATION NUMBER
CRD42021231656.
Topics: Abortion, Induced; Female; Health Personnel; Humans; Pregnancy; Qualitative Research; Self-Testing
PubMed: 35228285
DOI: 10.1136/bmjopen-2021-054120 -
Journal of Obstetrics and Gynaecology :... Dec 2024Vaginal bleeding during pregnancy has been recognised as a significant risk factor for adverse pregnancy outcomes. This study aimed to investigate the association... (Meta-Analysis)
Meta-Analysis Review
Vaginal bleeding during pregnancy has been recognised as a significant risk factor for adverse pregnancy outcomes. This study aimed to investigate the association between vaginal bleeding during the first trimester of pregnancy and clinical adverse effects using a systematic review and meta-analysis. Databases of Scopus, Web of Science, PubMed (including Medline), Cochrane Library and Science Direct were searched until June of 2023. Data analysis using statistical test fixed- and random-effects models in the meta-analysis, Cochran and meta-regression. The quality of the eligible studies was assessed by using the Newcastle-Ottawa Scale checklist (NOS). A total of 46 relevant studies, with a sample size of 1,554,141 were entered into the meta-analysis. Vaginal bleeding during the first trimester of pregnancy increases the risk of preterm birth (OR: 1.8, CI 95%: 1.6-2.0), low birth weight (LBW; OR: 2.0, CI 95%: 1.5-2.6), premature rupture of membranes (PROMs; OR: 2.3, CI 95%: 1.8-3.0), abortion (OR: 4.3, CI 95%: 2.0-9.0), stillbirth (OR: 2.5, CI 95%: 1.2-5.0), placental abruption (OR: 2.2, CI 95%: 1.4-3.3) and placenta previa (OR: 1.9, CI 95%: 1.5-2.4). Vaginal bleeding in the first trimester of pregnancy is associated with preterm birth, LBW, PROMs, miscarriage, stillbirth, placental abruption and placenta previa. Therefore, physicians or midwives need to be aware of the possibility of these consequences and manage them when they occur.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Stillbirth; Premature Birth; Abruptio Placentae; Placenta Previa; Placenta; Pregnancy Outcome; Abortion, Spontaneous; Uterine Hemorrhage
PubMed: 38305047
DOI: 10.1080/01443615.2023.2288224 -
Annals of Global Health 2022Disparities in health outcomes between immigrant and native-origin populations, particularly pregnant women, pose significant challenges to healthcare systems. The aim... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Disparities in health outcomes between immigrant and native-origin populations, particularly pregnant women, pose significant challenges to healthcare systems. The aim of this systematic-review and meta-analysis was to investigate the risk of adverse pregnancy outcomes among immigrant-women compared to native-origin women in the host country.
METHODS
PubMed (including MEDLINE), Scopus, and Web of Science were searched to retrieve studies published in English language up to September 2020. All observational studies examining the prevalence of at least one of the short-term single pregnancy outcomes for immigrants who crossed international borders compared to native-origin pregnant population were included. The meta-prop method was used for the pooled-estimation of adverse pregnancy-outcomes' prevalence. For pool-effect estimates, the association between the immigration-status and outcomes of interest, the random-effects model was applied using the model described by DerSimonian and Laird. I statistic was used to assess heterogeneity. The publication bias was assessed using the Harbord-test. Meta-regression was performed to explore the effect of geographical region as the heterogeneity source.
FINDINGS
This review involved 11 320 674 pregnant women with an immigration-background and 56 102 698 pregnant women as the native-origin population. The risk of emergency cesarean section (Pooled-OR = 1.1, 95%CI = 1.0-1.2), shoulder dystocia (Pooled-OR = 1.1, 95%CI = 1.0-1.3), gestational diabetes mellites (Pooled-OR = 1.4, 95%CI = 1.2-1.6), small for gestational age (Pooled-OR=1.3, 95%CI = 1.1-0.4), 5-min Apgar less than 7 (Pooled-OR = 1.2, 95%CI = 1.0-1.3) and oligohydramnios (Pooled-OR = 1.8, 95%CI = 1.0-3.3) in the immigrant women were significantly higher than those with the native origin background. The immigrant women had a lower risk of labor induction (Pooled-OR = 0.8, 95%CI = 0.7-0.8), pregnancy induced hypertension (Pooled-OR = 0.6, 95%CI = 0.5-0.7) preeclampsia (Pooled-OR = 0.7, 95%CI = 0.6-0.8), macrosomia (Pooled-OR = 0.8, 95%CI = 0.7-0.9) and large for gestational age (Pooled-OR = 0.8, 95%CI = 0.7-0.8). Also, the risk of total and primary cesarean section, instrumental-delivery, preterm-birth, and birth-trauma were similar in both groups. According to meta-regression analyses, the reported ORs were not influenced by the country of origin.
CONCLUSION
The relationship between the immigration status and adverse perinatal outcomes indicated a heterogenous pattern, but the immigrant women were at an increased risk of some important adverse pregnancy outcomes. Population-based studies with a focus on the various aspects of this phenomena are required to explain the source of these heterogenicities.
Topics: Cesarean Section; Diabetes, Gestational; Emigration and Immigration; Female; Humans; Infant, Newborn; Pregnancy; Pregnancy Outcome; Premature Birth
PubMed: 35854922
DOI: 10.5334/aogh.3591 -
European Journal of Obstetrics &... Sep 2023Incarcerated gravid uterus (IGU) is a serious complication of pregnancy that leads to adverse obstetric outcomes. The aim of this review was to describe this entity in... (Review)
Review
Incarcerated gravid uterus (IGU) is a serious complication of pregnancy that leads to adverse obstetric outcomes. The aim of this review was to describe this entity in detail. We also aimed to understand if pregnancies with predisposing risk factors that increase the risk of developing IGU had a difference in their clinical manifestations, treatment, and obstetric outcomes. The PubMed, MEDLINE, Embase, Scopus databases and clinicaltrials.gov were searched from inception to July 2023. Case reports and series that provided all the details of the pregnancy and IGU outcome were included. Study quality and risk of bias were assessed using a tool that is an adaptation from criteria listed by Pierson, Bradford Hills and Newcastle Ottawa scale modification. Patients with the condition of interest included in this review were grouped into those with documented, identified risk factors and no risk factors. The two groups were compared to understand the difference in obstetric outcome and presentation of IGU. Data were analyzed and summarized descriptively, categorical variables were assessed by chi-squared test or Fisher's exact test, and continuous variables by the Wilcoxon Mann Whitney test. Of 236 articles found, 62 articles with 80 cases were included in the final analysis. The median age was 32 [27-35] years. The median gestational age of diagnosis was 17 [14-26] weeks. The most common risk factor was fibroids (N = 22, 27.5 %). Most common presentation was urinary complaints and lower abdomen pain (N = 47, 58.6 %). Twenty-seven patients (33.6 %) needed more than one visit for the diagnosis to be made. Conservative management was the first step to treat IGU in most patients. Most common complication was fetal malpresentation (N = 13, 40.6 %). Patients with or without risk factors developing IGU had no statistical difference in- parity, median gestational age of diagnosis, delay in diagnosis, increased chance of misdiagnosis, management of IGU or in obstetric outcome (all p > 0.05). It is important to recognize this entity early to prevent obstetric complications especially when patients report urinary retention and abdomen pain. The presence of risk factors does not change the management course or obstetric outcome in patients with IGU. Hence it is reasonable to start with conservative management of IGU regardless of presence of risk factors or the gestational age of diagnosis, in clinical practice.
PubMed: 37664181
DOI: 10.1016/j.eurox.2023.100227 -
BMJ Global Health Aug 2022Racial discrimination has been consistently linked to various health outcomes and health disparities, including studies associating racial discrimination with patterns... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Racial discrimination has been consistently linked to various health outcomes and health disparities, including studies associating racial discrimination with patterns of racial disparities in adverse pregnancy outcomes. To expand our knowledge, this systematic review and meta-analysis assesses all available evidence on the association between self-reported racial discrimination and adverse pregnancy outcomes.
METHODS
Eight electronic databases were searched without language or time restrictions, through January 2022. Data were extracted using a pre-piloted extraction tool. Quality assessment was conducted using the Newcastle-Ottawa Scale (NOS), and across all included studies using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random effects meta-analyses were performed on preterm birth and small for gestational age. Heterogenicity was assessed using Cochran's χ test and I statistic.
RESULTS
Of 13 597 retrieved records, 24 articles were included. Studies included cohort, case-control and cross-sectional designs and were predominantly conducted in the USA (n=20). Across all outcomes, significant positive associations (between experiencing racial discrimination and an adverse pregnancy event) and non-significant associations (trending towards positive) were reported, with no studies reporting significant negative associations. The overall pooled odds ratio (OR) for preterm birth was 1.40 (95% CI 1.17 to 1.68; 13 studies) and for small for gestational age it was 1.23 (95% CI 0.76 to 1.99; 3 studies). When excluding low-quality studies, the preterm birth OR attenuated to 1.31 (95% CI 1.08 to 1.59; 10 studies). Similar results were obtained across sensitivity and subgroup analyses, indicating a significant positive association.
CONCLUSION
These results suggest that racial discrimination has adverse impacts on pregnancy outcomes. This is supported by the broader literature on racial discrimination as a risk factor for adverse health outcomes. To further explore this association and underlying mechanisms, including mediating and moderating factors, higher quality evidence from large ethnographically diverse cohorts is needed.
Topics: Cohort Studies; Cross-Sectional Studies; Female; Humans; Infant, Newborn; Pregnancy; Pregnancy Outcome; Premature Birth; Racism
PubMed: 35918071
DOI: 10.1136/bmjgh-2022-009227 -
Journal of Clinical Medicine Jan 2022This systematic review and meta-analysis aimed to assess evidence on the effects of aquatic exercise in pregnant women. The search included the following databases:... (Review)
Review
This systematic review and meta-analysis aimed to assess evidence on the effects of aquatic exercise in pregnant women. The search included the following databases: Medline-PubMed, Web of science, PEDro, Scopus and SPORTDiscus databases. Seventeen randomized controlled trials were included ( = 2439, age 20-39 years; 31.30 ± 1.30 years). The systematic review carried out has indicated that aquatic exercise in pregnant women appears to have positive effects on preventing excessive maternal weight gain, improving maternal body image, as well as promoting healthy behavior, decreasing medical leave due to lower back pain during pregnancy, preventing gestational depression by improving maternal glucose tolerance levels, and reducing O'Sullivan test values. The Physiotherapy Evidence Database was used to evaluate the quality of the methodology of the selected studies, which were found to present an average methodological quality (PEDro scale: 5.05 points). Meta-analysis showed that aquatic exercise in pregnant women appears to have positive effects in the prevention of excessive maternal weight gain (mean difference -1.66 kg, 95% CI -2.67 to -0.66) and also to reduce birth weight mean differences (-89.13 g, 95% CI -143.18 to -35.08). The practice of aquatic exercise is appropriate throughout pregnancy. However, more research is needed to build more solid knowledge on the benefits of aquatic physical exercise on physical fitness (endurance, flexibility, agility and strength).
PubMed: 35159953
DOI: 10.3390/jcm11030501